Since the advent of blue gallium nitride (GaN)-based light emitting diodes (LEDs), they have been employed in technologies such as displays and general lighting (e.g., white-light LEDs). GaN-based blue LEDs are currently used for backlighting of LCD displays. The current technology, which is based on GaN-based thin-films grown on aluminum oxide (Al2O3), however, has several detrimental shortcomings. As the resolution of LCD display increases, there is a greater need for surface area backlighting. When using inorganic LEDs, backlighting is provided either by placing the LEDs directly behind the display or on the edge. Both these LED placements impose serious limitations on the manufacture of high-resolution and high-contrast displays. While the former method helps with better contrast, it makes the displays thicker and more expensive. The latter method, in conjunction with waveguiding, may reduce the thickness of the displays, but does not help to improve the contrast specified for high-resolution displays.
On the other hand, organic light emitting diodes (OLEDs) have been suggested to solve the rigidness problem of inorganic LEDs and are already in high demand due to their mechanical properties and their potential for high contrast LCD displays.